Perspetivas futuras

Tendo em conta as limitações e as consequências que advém da aplicação de um modelo desta natureza, surge a necessidade de reforçar este estudo com uma análise mais detalhada dos custos inerentes à implementação do mesmo: uma análise financeira que avalie os custos associados à utilização destas infraestruturas já existentes.

Com o intuito de completar a análise realizada pode ainda ser alargado o estudo à avaliação das poupanças a nível ambiental através do modelo cuja importância cresceu nos últimos anos - Green VRP. Estudar os impactos ambientais associados a um modelo cuja otimização de tempo e quilómetros percorridos pode trazer novos inputs significativos à comunidade científica. Por um lado, carecem estudos multiobjectivo (otimização económica e redução do impacto ambiental, por exemplo), por outro lado confere uma solidez ao modelo por considerar mais variáveis que podem afetar o sistema. Existe ainda um leque de oportunidades de estudo como a definição de novas frequências de recolha para distribuir melhor os pontos de recolha, garantido que estes são coletados no tempo devido, poupando ainda mais ineficiências a nível do tempo efetuado. Isto permite impedir que haja frequências com poucas rotas, como verificado na análise de agregação de frequências, que possam gerar alguns problemas a nível da definição de horários dos colaboradores. Em alternativa, pode também ser estudada a possibilidade de aumentar a capacidade dos contentores com maior procura, de forma a não forçar a recolha de todos os ecopontos de uma única freguesia mais cedo do que o tempo previsto e, consequentemente, aumentar a percentagem da ocupação do veículo.

Numa segunda instância, pode ser ainda equacionada a aplicação do modelo apenas com os depósitos com maior nível de intervenção e percentagem de utilização – CTRO, Óbidos e Rio Maior –, por forma a reduzir possíveis custos associados à ocupação de mais infraestruturas, apesar de poder implicar o acréscimo no número de quilómetros percorridos.

Numa terceira perspetiva, de modo a poder evitar os constrangimentos sociais mencionados associados ao modelo, surgem duas perspetivas de estudo. Por um lado, a análise operacional da sincronização das rotas e horários dos motoristas, na medida em que pode haver a necessidade de efetuar uma rota de seguida (ou no dia seguinte) com começo no mesmo ponto de término da rota anterior, não compensando a deslocação do motorista até à base de veículos inicial. Esta análise é essencial, pois não é claro que possa

compensar a realização destas rotas extra, ao poder implicar um acréscimo excessivo na quilometragem. Do ponto de vista contrário, o pernoitar do motorista e ajudante, além de acarretar alguns custos de estadia, levanta ainda questões de carácter social.

Por outro lado, pode ser estudada a possibilidade de implementar um modelo MDVRP

with inter-depot routes que, ao invés dos veículos terminarem as suas rotas no ponto

distinto do inicial, estes têm uma paragem a certa altura durante a rota que permite descarregar o veículo (nas Estações de Transferência) e voltar à realização do percurso com a capacidade do veículo totalmente renovada, terminando no mesmo ponto de começo. Este modelo evita os problemas associados à distância a que os motoristas ficam dos seus domicílios, ao passo que admite na mesma a existência de novos depósitos de descarga, mas que não servem como bases de veículos.

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